I've been divorced from DD's dad for 5 years but stayed close with the in laws.
ExFIL sadly passed away in the summer and lovely MIL was worried she'd be lonely at Christmas so I accepted when she invited me & DD for Christmas Dinner. Trouble is its ExH's turn to be with DD so we're all going to be there (including the OW who he's still with).
We get on ok when we have to but I can think of a million people I'd rather spend the day with (Boris allowing) but I'm doing it for ExMIL & DD and as I keep telling myself its just another dinner and I can make up for it another time...
Argh!!!